The application of LbL-microcarriers for the treatment of chronic inflammation: monitoring the impact of LbL-microcarriers on cell viability.

Layer-by-Layer (LbL) coated microcarriers provide a multifunctional drug delivery system for therapeutic substances into specific cells. Inflammatory cells as polymorphonuclear leukocytes (PMNs) represent a particularly promising target for LbL-microcarriers transporting anti-inflammatory substances such as α1 -antitrypsin (AT). They facilitate a local, low-dose and time-controlled application of the assembled therapeutic to effectively inhibit destructive enzymes provided by PMNs. But besides therapeutic effects, microcarriers themselves are not expected to affect cell viability. Thus, the present study emphasizes the investigation of LbL-microcarriers regarding their necrotic or apoptotic influence on inflammatory cells. The detection of mitochondrial membrane potential changes, reporting the induction of cellular apoptosis, was completed by the detection of apoptotic changes of the nucleus and lactate dehydrogenase release reporting potential necrotic influences. Investigations of microcarrier interactions with HL-60 cells and blood-isolated PMNs show very low influence on necrosis and, in case of AT-functionalized microcarriers, even a prolonged maintenance of mitochondrial membrane potential underlining the high potential of LbL-microcarriers.

Detection of an activated JAK3 variant and a Xq26.3 microdeletion causing loss of PHF6 and miR-424 expression in myelodysplastic syndromes by combined targeted next generation sequencing and SNP array analysis.

Myelodysplastic syndromes (MDS) are hematopoietic disorders characterized by ineffective hematopoiesis and progression to acute leukemia. In patients ineligible for hematopoietic stem cell transplantation, azacitidine is the only treatment shown to prolong survival. However, with the availability of a growing compendium of cancer biomarkers and related drugs, analysis of relevant genetic alterations for individual MDS patients might become part of routine evaluation. Therefore and in order to cover the entire bone marrow microenvironment involved in the pathogenesis of MDS, SNP array analysis and targeted next generation sequencing (tNGS) for the mostly therapy relevant 46 onco- and tumor-suppressor genes were performed on bone marrow biopsies from 29 MDS patients. In addition to the detection of mutations known to be associated with MDS in NRAS, KRAS, MPL, NPM1, IDH1, PTPN11, APC and MET, single nucleotide variants so far unrelated to MDS in STK11 (n=1), KDR (n=3), ATM (n=1) and JAK3 (n=2) were identified. Moreover, a recurrent microdeletion was detected in Xq26.3 (n=2), causing loss of PHF6 expression, a potential tumor suppressor gene, and the miR-424, which is involved in the development of acute myeloid leukemia. Finally, combined genetic aberrations affecting the VEGF/VEGFR pathway were found in the majority of cases demonstrating the diversity of mutations affecting different nodes of a particular signaling network as an intrinsic feature in MDS patients. We conclude that combined SNP array analyses and tNGS can identify established and novel therapy relevant genomic aberrations in MDS patients and track them in a clinical setting for individual therapy selection.